Lu Shu, Jiang Jun, Yang Hai, Zhang Ying-Jie, Pei Dan-Ni, Chen Jie-Jie, Yu Yan
CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science & Technology of China, Hefei 230026, China.
School of Metallurgy and Environment, Central South University, Changsha, Hunan 410083, China.
ACS Nano. 2020 Aug 25;14(8):10438-10451. doi: 10.1021/acsnano.0c04309. Epub 2020 Jul 27.
Rechargeable batteries are promising platforms for sustainable development of energy conversion and storage technologies. Highly efficient multifunctional electrodes based on bimetallic sulfides for rechargeable batteries are extremely desirable but still challenging to tailor with controllable phase and structure. Here, we report a colloidal strategy to fabricate FeCo-based bimetallic sulfides on reduced graphene oxide (rGO), which are expected to display highly efficient oxygen electrocatalysis and sodium storage performances. Specifically, as-screened FeCoS nanosheets (NSs) on rGO originating from suitable tailoring of the CoS matrix with Fe at the atomic level exhibited a very low potential difference (0.77 V) at 10 mA cm and negligible voltage loss after 200 cycles as an air electrode for Zn-air batteries. For Na-ion batteries, FeCoS NS/rGO demonstrated a superior high-rate capability (188 mAh g at 20 A g) with long-term cycling stability. The bifunctional electrocatalytic property and sodium storage performance are attributed to not only the synergistic effect of Fe/Co but also the optimized catalytic activity and ion transport ability by the rGO hybrid. This work demonstrates the potential applications of FeCo-based bimetallic sulfides as efficient electrode materials for both rechargeable Zn-air and Na-ion batteries.
可充电电池是能源转换和存储技术可持续发展的有前景的平台。基于双金属硫化物的高效多功能可充电电池电极极具吸引力，但要定制具有可控相和结构的电极仍具有挑战性。在此，我们报道了一种胶体策略，用于在还原氧化石墨烯（rGO）上制备基于铁钴的双金属硫化物，预计其将展现出高效的氧电催化和钠存储性能。具体而言，通过在原子水平用铁对硫化钴基质进行适当剪裁，在rGO上筛选出的FeCoS纳米片（NSs）作为锌空气电池的空气电极，在10 mA cm时显示出非常低的电位差（0.77 V），并且在200次循环后电压损失可忽略不计。对于钠离子电池，FeCoS NS/rGO表现出优异的高倍率性能（在20 A g时为188 mAh g）以及长期循环稳定性。这种双功能电催化性能和钠存储性能不仅归因于铁/钴的协同效应，还归因于rGO杂化物优化的催化活性和离子传输能力。这项工作展示了基于铁钴的双金属硫化物作为可充电锌空气电池和钠离子电池的高效电极材料的潜在应用。
